Meanwhile the conditions of the two victims, according to a Stony Brook University Hospital spokeswoman, are different than what media outlets, including the News-Review, had initially reported by Southampton Town police last night.

It was originally reported that Abner Canel, 18, was listed in critical condition and Rolando Perez, 40, was listed in stable condition. However as of Wednesday night, Mr. Canel was listed in serious condition, and Mr. Perez in fair condition.

Their conditions remained serious and fair as of Thursday morning.

A Stony Brook University Hospital official said Southampton Town police most likely mistakenly swapped the identities of the victims when reporting their names.

According to Tony Cuiffo, area director with the U.S. Occupational Safety and Hazard Administration, the regulatory agency has up to six months to complete an investigation, though, he added, it’s “too premature in the investigation at this time to say if the employer did violate” any safety rules.

National Grid gas company crews were working on the house’s gas lines Thursday morning, though crew members on scene declined to comment.

Dr. Edward Kush, who lives in a condominium complex directly behind the house, said he was one of the first people to arrive on scene yesterday.

“I heard a loud bang and smelled smoke,” he said. “I ran over there and the place immediately burst into flames.”

Before emergency crews arrived, he said neighbors helped assist the victims. Dr. Kush said he spoke to Mr. Perez as he was walking away from the burning home.

“I looked right at him and asked, ‘Are you OK?’” Mr. Kush said. “His face was bloody, but he nodded ‘yes.’”

The explosion damaged eight condos, including Mr. Kush’s, who said the pressure from the blast caused the units to shift slightly from their foundation.

Gilbert Quvus of Riverhead, who was conducting traffic control for National Grid, said at least a half dozen people drove by the home to observe the damage before 8:30 a.m.

One of them was John Carvis, who lives in Westhampton and heard the emergency call come over his scanner Wednesday afternoon.

“I just hope the people get better,” he said. “This is tragic.”

In his 12 years on the job, Mr. Quvus said this is the worst accident he’s ever seen.

“It is amazing more people didn’t get hurt,” he said.

Captions: Firefighters at the scene of the explosion in Water Mill. (Credit: The Southampton Press/Dana Shaw). The site of a Water Mill explosion. (Credit: Christine Fuge)